[Defy Android Development] htto:
Well, that CONFIG-option is set in the mapphone_defconfig.

host
T: Bus=01 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=480 MxCh= 3
B: Alloc= 0/800 us ( 0%), #Int= 0, #Iso= 0
D: Ver= 2.00 Cls=09(hub ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1
P: Vendor=1d6b ProdID=0002 Rev= 3.00
S: Manufacturer=Linux 3.0.101-04284-g20e53be-dirty ehci_hcd
S: Product=OMAP-EHCI Host Controller
S: SerialNumber=ehci-omap.0
C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr= 0mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub
E: Ad=81(I) Atr=03(Int.) MxPS= 4 Ivl=256ms

device
T: Bus=01 Lev=01 Prnt=01 Port=02 Cnt=01 Dev#= 2 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=ff(vend.) Sub=ff Prot=ff MxPS=64 #Cfgs= 1
P: Vendor=22b8 ProdID=40e6 Rev= 0.02
S: Manufacturer=Motorola Inc.
S: Product=Motorola Phone ()
C:* #Ifs= 2 Cfg#= 1 Atr=c0 MxPwr=500mA
I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=usb_ipc_data
E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=ff Prot=ff Driver=usb_ipc_data
E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms

endpoints probably being handled by musb/musb_gadget_ep0.c

INTERFACE_3 probably refers to the sysfs device 1-3

1-3:Motorola Phone ()

1-3:1.0 < Motorola IPC Data Interface

1-3:1.1 < Motorola IPC Log Interface

So xx:1:001:0 below should be the IPC Data Interface

[dev->host: last bulk in] normal data
c0913830 890551514 C Bi:1:002:1 0 36 = 0 [ .. ]
c0913830 890553070 S Bi:1:002:1 -115 15548 <

[host->dev: SET_FEATURE TEST_MODE INTERFACE_3 ] set feature test_mode
cae22e00 891325898 S Co:1:001:0 s 23 03 0002 0003 0000 0
cae22e00 891325928 C Co:1:001:0 0 0

[dev->host: bulk error] signalling?
c0913830 891330139 C Bi:1:002:1 -71 0

[dev->host: interrupt] signalling?
dd79f000 891381989 C Ii:1:001:1 -2:2048 0

[ 154491577us / ~154s pause]

[event from modem starting?]

[dev->host: GET_STATUS INTERFACE_1-3] status reply
caf46c00 1045873566 S Ci:1:001:0 s a3 00 0000 0001 0004 4 <
caf46c00 1045873596 C Ci:1:001:0 0 4 = 00010000
caf46c00 1045873627 S Ci:1:001:0 s a3 00 0000 0002 0004 4 <
caf46c00 1045873627 C Ci:1:001:0 0 4 = 00010000
caf46c00 1045873627 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
caf46c00 1045873627 C Ci:1:001:0 0 4 = 00010100

[dev->host: interrupt] signalling?
dd79f000 1045982941 S Ii:1:001:1 -115:2048 4 <

[dev->host: GET_STATUS INTERFACE_3] get port status
ce408100 1045983002 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
ce408100 1045983032 C Ci:1:001:0 0 4 = 01050100

[driver didn't expect anything and kills remote wakeup? the ep_xy's have autosuspend disabled, the interface doesn't seem to]

[host->dev: CLEAR_FEATURE REM_WAKEUP INTERFACE_3] clear remote wakeup
ce408100 1045983032 S Co:1:001:0 s 23 01 0010 0003 0000 0
ce408100 1045983032 C Co:1:001:0 0 0

[dev->host: GET_DESCRIPTOR 0100] get device descriptor device 0
ce408100 1045983124 S Ci:1:002:0 s 80 06 0100 0000 0040 64 <
ce408100 1045987152 C Ci:1:002:0 -71 0

[error -71 re-occuring]

[issuing reset?]

[host->dev: CLEAR_FEATURE ENDPOINT_HALT INTERFACE_3] clear endpoint halt
c7704f80 1046217316 S Co:1:001:0 s 23 01 0001 0003 0000 0
c7704f80 1046217346 C Co:1:001:0 0 0

just for reference the working setup part before the bulk data exchange

[host->dev: ] set feature test_mode
d8ce5d80 855159668 S Co:1:001:0 s 23 03 0002 0003 0000 0
d8ce5d80 855159729 C Co:1:001:0 0 0
[dev->host:] reply? signalling?
c0913830 855163941 C Bi:1:002:1 -71 0
dd79f000 855198578 C Ii:1:001:1 -2:2048 0
[dev->host:] status reply
d8c0ba80 856665863 S Ci:1:001:0 s a3 00 0000 0001 0004 4 <
d8c0ba80 856665894 C Ci:1:001:0 0 4 = 00010000
d8c0ba80 856665924 S Ci:1:001:0 s a3 00 0000 0002 0004 4 <
d8c0ba80 856665924 C Ci:1:001:0 0 4 = 00010000
d8c0ba80 856665924 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
d8c0ba80 856665924 C Ci:1:001:0 0 4 = 07050000
[dev->host:] signalling?
dd79f000 856665955 S Ii:1:001:1 -115:2048 4 <
[dev->host:] status reply
d8c0ba80 856665955 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
d8c0ba80 856665985 C Ci:1:001:0 0 4 = 07050000
[host->dev:] set feature test_mode
d8c0ba80 856665985 S Co:1:001:0 s 23 01 0002 0003 0000 0
d8c0ba80 856665985 C Co:1:001:0 0 0
[dev->host:]
d8c0ba80 856704956 S Ci:1:001:0 s a3 00 0000 0003 0004 4 <
d8c0ba80 856705963 C Ci:1:001:0 0 4 = 03050400
[host->dev:] set feature
d8c0ba80 856728455 S Co:1:001:0 s 23 01 0012 0003 0000 0
d8c0ba80 856728485 C Co:1:001:0 0 0
[dev->host:] endpoint descriptor reply?
d8c0ba80 856728516 S Ci:1:002:0 s 80 00 0000 0000 0002 2 <
d8c0ba80 856728730 C Ci:1:002:0 0 2 = 0100

Basically I suspect failure in the musb stack. Though, I'm by no means an USB expert. And unfortunately I'm unable to boot a non-otg/musb kernel :/